1. Field of the Invention
The present invention relates to a storage container for a dental adhesive used for treatment of dental caries in dentistry.
2. Description of the Related Art
“Tooth decay” generally called dental caries is a common disease in dentistry, and many people experience tooth decay regardless of age or sex. When tooth decay advances, the tooth decay does not naturally heal but needs to be treated by a dentist. A widely used method for the treatment is to shave a tooth decay portion down with a dental grinding tool to form a cavity, fill a dental restoratives such as composite resin into the cavity, and reproduce natural tooth anatomy. The composite resin is mainly classified into chemical polymerization resin and photo polymerization resin by a difference in curing method, and these resins are used for different applications.
The composite resin cannot adhere to teeth substance by itself, and requires a dental adhesive applied between the composite resin and the teeth substance. In recent years, technical developments in the field of dental adhesives have been rapidly made, and firm adhesion to adherend such as metal, ceramic, or composite resin has been achieved in addition to firm adhesion to the teeth substance. Conventionally, a plurality of steps such as etching, priming, and bonding are required during use of an adhesive. Liquid materials such as adhesives stored in storage containers for the respective steps are dropped onto different wells on a dish, and applied to an application site in order according to a procedure. However, driven by users' needs for a simplified operation procedure and a stable adhesive property, a self-etching primer used in a combined step of etching and priming, and an all-in-one adhesive used in a combined step of etching, priming, and bonding have been developed to improve operability and an adhesive property and reduce the number of storage containers for storing liquid materials. However, the all-in-one adhesive or the like does not totally replace, but a two liquid mixing type adhesive used by dropping desired amounts of liquid materials from two storage containers in order onto the same well on a dish so as to contact with each other and mixing the liquid materials has been also widely used.
A trace amount of dental adhesive is applied at one time, and thus too large an amount of drops from a storage container increase an amount of waste and thus increase cost. Thus, to reliably control a trace amount of drops, a shape or a diameter of a discharge port of a nozzle located at a distal end of the container, and a length and a hole diameter of a channel connecting to the nozzle are strictly controlled. Particularly, more strict control is performed for achieving designed performance with a two liquid mixing type adhesive because amounts of drops of adhesives and a mixing ratio thereof are important. Since a trace amount of adhesive is applied at one time as described above and also there is an expiration date, a storage container for the adhesive is naturally small, and a height from a bottom to a cap is 5 cm maximum. Thus, to drop the adhesive onto a dish, the storage container is generally turned downward and pressed at side surfaces by a thumb and an index finger holding the side surfaces. This pressing operation is generally called “squeeze”.